The present invention relates to a method of analysing ions, a method of mass spectrometry, an analytical device and a mass spectrometer.
U.S. Pat. No. 6,992,283 (Micromass) discloses an arrangement wherein ions are passed through an ion mobility separator and are then mass analysed by a Time of Flight mass analyser.
It is known to perform asynchronous IMS-Time of Flight acquisitions wherein the Time of Flight experimental time determines the ion mobility spectrometry or separation digitisation rate.
One problem with conventional mass spectrometers comprising an ion mobility separator or spectrometer in combination with a Time of Flight mass analyser is that the effective digitisation of an ion peak eluting from an ion mobility spectrometry or separation device by the Time of Flight mass analyser may be limited.
It is known to synchronise an orthogonal acceleration Time of Flight pusher with the release of ions into an ion mobility spectrometry or separation device. This approach is, however, limited by the need to accurately synchronise the pusher and ion mobility spectrometry or separation cycle times and requires additional electronics. This approach also introduces the possibly of additional systematic errors in mobility calibration due to any lack of synchronicity.
FIG. 10 of US 2011/0062323 (Micromass) discloses an arrangement comprising an ion mobility separator 26 and a collision cell 27 arranged downstream of the ion mobility separator 26. It is contemplated that the collision cell 27 may comprise an Electron Transfer Dissociation (“ETD”) collision cell. The collision cell 27 comprises a plurality of ring electrodes and an arrangement is contemplated wherein travelling or transient DC voltages are applied to the ring electrodes and a feedback control mechanism is used to control the effective velocity at which the transient DC voltages are translated along the length of the collision cell 27 in order to optimise the Electron Transfer Dissociation fragmentation and charge reduction process.
US 2003/0001087 (Fuhrer) discloses a time of flight mass spectrometer for monitoring fast processes using an interleaved timing scheme and a position sensitive detector.
US 2007/0278397 (Micromass) discloses providing an ion guide downstream of an ion mobility spectrometer. A plurality of axial potential wells are created in the ion guide to maintain the fidelity of ions received from the ion mobility spectrometer.
US 2010/0128246 (Heizmann) discloses an optoelectronic sensor for the measurement of distances.
GB-2497948 (Makarov) discloses a collision cell for tandem mass spectrometry.
GB-2391697 (Micromass) discloses a mass spectrometer having an ion guide which receives ions and emits ions in a synchronised manner with an orthogonal acceleration Time of Flight mass analyser.
GB-2397433 (Micromass) discloses a mass spectrometer wherein ions from a pulsed ion source are received by an ion guide in which multiple trapping regions are created.
GB-2451149 (Micromass) discloses a dual mode ion mobility mass analyser device.
GB-2421840 (Micromass) discloses a mass spectrometer comprising an ion guide located downstream of an ion mobility spectrometer.
GB-2485667 (Micromass) discloses a mass spectrometer comprising a gas phase ion-neutral reaction device arranged to perform Hydrogen-Deuterium exchange.
It is desired to provide an improved mass spectrometer and method of mass spectrometry.